<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <style>
      * {
        box-sizing: border-box;
        margin: 0;
        border: 0;
        font-family: Helvetica, sans-serif;
      }

      :root {
        --color-green: 130deg;
        --color-blue: 200deg;
        --color-purple: 250deg;

        --opacity-100: 100%;
        --opacity-80: 80%;
        --opacity-70: 70%;
        --opacity-50: 50%;
        --opacity-30: 30%;

        --lightness-60: 60%;
        --lightness-40: 40%;
        --lightness-30: 30%;
        --lightness-20: 20%;
        --lightness-10: 10%;

        --saturation-100: 100%;
        --saturation-80: 80%;
        --saturation-70: 70%;
        --saturation-50: 50%;
        --saturation-30: 30%;

        --green-opacity-100: hsl(
          var(--color-green),
          var(--saturation-100),
          var(--lightness-60),
          var(--opacity-100)
        );
        --green-opacity-80: hsl(
          var(--color-green),
          var(--saturation-100),
          var(--lightness-60),
          var(--opacity-80)
        );
        --green-opacity-70: hsl(
          var(--color-green),
          var(--saturation-100),
          var(--lightness-60),
          var(--opacity-70)
        );
        --green-opacity-50: hsl(
          var(--color-green),
          var(--saturation-100),
          var(--lightness-60),
          var(--opacity-50)
        );
        --green-opacity-30: hsl(
          var(--color-green),
          var(--saturation-100),
          var(--lightness-60),
          var(--opacity-30)
        );

        --blue-light-60: hsl(
          var(--color-blue),
          var(--saturation-100),
          var(--lightness-60),
          var(--opacity-100)
        );
        --blue-light-40: hsl(
          var(--color-blue),
          var(--saturation-100),
          var(--lightness-40),
          var(--opacity-100)
        );
        --blue-light-30: hsl(
          var(--color-blue),
          var(--saturation-100),
          var(--lightness-30),
          var(--opacity-100)
        );
        --blue-light-20: hsl(
          var(--color-blue),
          var(--saturation-100),
          var(--lightness-20),
          var(--opacity-100)
        );
        --blue-light-10: hsl(
          var(--color-blue),
          var(--saturation-100),
          var(--lightness-10),
          var(--opacity-100)
        );

        --purple-sat-100: hsl(
          var(--color-purple),
          var(--saturation-100),
          var(--lightness-60),
          var(--opacity-100)
        );
        --purple-sat-80: hsl(
          var(--color-purple),
          var(--saturation-80),
          var(--lightness-60),
          var(--opacity-100)
        );
        --purple-sat-70: hsl(
          var(--color-purple),
          var(--saturation-70),
          var(--lightness-60),
          var(--opacity-100)
        );
        --purple-sat-50: hsl(
          var(--color-purple),
          var(--saturation-50),
          var(--lightness-60),
          var(--opacity-100)
        );
        --purple-sat-30: hsl(
          var(--color-purple),
          var(--saturation-30),
          var(--lightness-60),
          var(--opacity-100)
        );
      }

      main {
        width: 100vw;
        height: 100vh;
        background-color: #000000;
        display: grid;
        align-content: center;
        justify-content: center;
        grid-template-columns: 1fr 1fr 1fr;
        gap: 12px;
        padding: 24px;
        /* row-gap: 3px; */
      }

      .bar {
        width: 100%;
        height: 80px;
        display: flex;
        align-items: center;
        justify-content: center;
        color: #ffffff;
      }

      .green .bar:nth-child(1) {
        background-color: var(--green-opacity-100);
      }
      .green .bar:nth-child(2) {
        background-color: var(--green-opacity-80);
      }
      .green .bar:nth-child(3) {
        background-color: var(--green-opacity-70);
      }
      .green .bar:nth-child(4) {
        background-color: var(--green-opacity-50);
      }
      .green .bar:nth-child(5) {
        background-color: var(--green-opacity-30);
      }

      .blue .bar:nth-child(1) {
        background-color: var(--blue-light-60);
      }
      .blue .bar:nth-child(2) {
        background-color: var(--blue-light-40);
      }
      .blue .bar:nth-child(3) {
        background-color: var(--blue-light-30);
      }
      .blue .bar:nth-child(4) {
        background-color: var(--blue-light-20);
      }
      .blue .bar:nth-child(5) {
        background-color: var(--blue-light-10);
      }

      .purple .bar:nth-child(1) {
        background-color: var(--purple-sat-100);
      }
      .purple .bar:nth-child(2) {
        background-color: var(--purple-sat-80);
      }
      .purple .bar:nth-child(3) {
        background-color: var(--purple-sat-70);
      }
      .purple .bar:nth-child(4) {
        background-color: var(--purple-sat-50);
      }
      .purple .bar:nth-child(5) {
        background-color: var(--purple-sat-30);
      }
    </style>
    <title>Document</title>
  </head>
  <body>
    <main>
      <div class="green">
        <div class="bar">hsl(130deg, 100%, 60%, 100%)</div>
        <div class="bar">hsl(130deg, 100%, 60%, 80%)</div>
        <div class="bar">hsl(130deg, 100%, 60%, 70%)</div>
        <div class="bar">hsl(130deg, 100%, 60%, 50%)</div>
        <div class="bar">hsl(130deg, 100%, 60%, 30%)</div>
      </div>
      <div class="blue">
        <div class="bar">hsl(200deg, 100%, 60%, 100%)</div>
        <div class="bar">hsl(200deg, 100%, 40%, 100%)</div>
        <div class="bar">hsl(200deg, 100%, 30%, 100%)</div>
        <div class="bar">hsl(200deg, 100%, 20%, 100%)</div>
        <div class="bar">hsl(200deg, 100%, 10%, 100%)</div>
      </div>
      <div class="purple">
        <div class="bar">hsl(250deg, 100%, 60%, 100%)</div>
        <div class="bar">hsl(250deg, 80%, 60%, 90%)</div>
        <div class="bar">hsl(250deg, 70%, 60%, 80%)</div>
        <div class="bar">hsl(250deg, 50%, 60%, 70%)</div>
        <div class="bar">hsl(250deg, 30%, 60%, 60%)</div>
      </div>
    </main>
  </body>
</html>
